| 摘要 |
PURPOSE:To enable the display of the speed of a motor and the direction of rotation thereof by inverting the waveform of an F/V conversion output in accordance with the direction of rotation of a two-phase digital tachometer. CONSTITUTION:Each output of a two-phase digital tachometer of a motor is given to lines 1 and 2 and applied further to an AND gate 3 and monostable multivibrators 4 and 5. Then NAND10 of outputs 6 and 8 is taken at the time of the rotation in the clockwise rotation, while NAND9 of outputs 6 and 7 is taken at the time of the rotation in the counterclockwise direction. Thereby the first and second of phases of a two-phase pulse is discriminated and a rotation pulse can be taken out for each direction of rotation. In an F/V conversion circuit, a monostable multivibrator 18 is set at the rise in the rotation pulse of a line 16, the output pulse of the vibrator is integrated, and an analog waveform is obtaind therefrom. According to this waveform, an operational amplifier 34 is made to conduct an operation of positive phase/inversion corresponding to the direction of rotation, and a positive or negative analog waveform is obtained therefrom. |
